The Pentagon has deployed drones to spy over U.S. territory for non-military missions over the past decade, but the flights have been rare and lawful, according to a new report. The report by a Pentagon inspector general, made public under a Freedom of Information Act request, said spy drones on non-military missions have occurred fewer than 20 times between 2006 and 2015 and always in compliance with existing law.

The report, which did not provide details on any of the domestic spying missions, said the Pentagon takes the issue of military drones used on American soil “very seriously.” A senior policy analyst for the ACLU, Jay Stanley, said it is good news no legal violations were found, yet the technology is so advanced that it’s possible laws may require revision. “Sometimes, new technology changes so rapidly that existing law no longer fit what people think are appropriate,” Stanley said. “It’s important to remember that the American people do find this to be a very, very sensitive topic.” READ MORE